While Belvedere is one of the tonier towns in Marin, its residents have the most time-consuming commutes of any workers in the county, according to a new report from the Metropolitan Transportation Commission.

It takes the average Belvedere resident 40.6 minutes to get to work, far outpacing the second-longest commute, San Anselmo’s 35.5 minutes, according to the report.

During the morning commute, drivers leaving Belvedere crawl along Tiburon Boulevard, and backups can sometimes seem never ending, city officials say.

“It’s a long and winding road into San Francisco,” said James Campbell, a Belvedere city councilman.

Last year the Belvedere City Council voted to contribute $15,000 to a study to unclog Tiburon Boulevard, the only point of access in and out of the peninsula for Belvedere residents. Money is on the way to do some work on that road, Campbell said. Improved ferry service by Golden Gate out of Tiburon and an ongoing school bus program to keep parents from mixing with commute and other traffic also is helping.

“Otherwise the commute time would be even higher,” Campbell said.

The data comes from the Metropolitan Transportation Commission’s Vital Signs program — vitalsigns.mtc.ca.gov — designed to give Bay Area residents a snapshot of key transportation, land use, environmental and economic policy trends.

Overall, Marin residents take 32.3 minutes to get to work, while Bay Area-wide the time is 31.6 minutes, according to the data. In 2011, the travel time in Marin was 27 minutes.

The commute data also breaks down times for those who use different modes to get to work. In Marin, solo drivers take 29.8 minutes to get to work, car poolers 33.5 minutes and those who take transit 58.1 minutes.

That is compared to Bay Area solo drivers who take 29 minutes to get to work, car poolers 32.9 minutes and transit users 50.8 minutes.

Among Marin’s cities and towns, San Rafael residents had the shortest commute at 28.4 minutes.

The data reveals 22.8 percent of Marin residents commute 15 minutes or less. Another 27.5 percent spend between 15 and 29 minutes commuting, while 20.2 percent take from 30 to 44 minutes to get to work. Thirteen percent take 45 to 59 minutes to get to their jobs, 12.4 percent take 60 to 89 minutes and 4.1 percent spend more than 90 minutes commuting.

“Since 2006 there has generally been a steady increase — the Great Recession notwithstanding — in travel times,” said John Goodwin, MTC spokesman.

The report notes more than 3.7 million Bay Area residents commute each day. Travel time has increased from 24 minutes in 1980 to about 32 minutes today, longer than ever for the region. While the commute time has grown, it is on par with other major metropolitan areas in the United States, according to the report.

Commuters who drive alone spend 29 minutes getting to work, while those on transit take 51 minutes to get to work on average.

<p/> <p>A massive highway bridge collapsed over the Italian city of Genoa during a rainstorm Tuesday, causing concrete and cars to fall several stories onto buildings and killing at least 11 people, according to a state run news agency.